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Anodize test

Could you tell me the best test to measure if my black anodize coating is well done?

Thanks,

Carlos Pongo
- Chatsworth, California
2002

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Good quality anodize can't be determined in a single test. It needs to be corrosion resistant, thus, the anodizer should be doing monthly panels to demonstrate that they are indeed producing a corrosion resistant anodize. It should be sealed to avoid color fading upon exposure to excesses of light, heat or certain chemicals. A typical seal integrity test is ASTM B136. A cheap, unsealed anodize will easily show up with this test. Lastly, the anodize should be a set thickness in order to maintain final, finished dimensions. In general a typical black anodize should be on the order of 1/2 to 1 mil thick. All specs such as MIL-A-8625 / MIL-PRF-8625 [on DLA] define quality anodize. Good luck....

Milt Stevenson, Jr.
Syracuse, New York
2002